This invention relates to a drive bearing lubrication device for a water injection propulsion vessel and more particularly to an improved front bearing support and lubrication arrangement for a water jet propulsion unit.
A wide variety of water vessels are propelled by jet propulsion units. These jet propulsion units include an impeller that is driven by an impeller shaft which extends forwardly through a bulkhead in the hull of the watercraft for driving connection to an internal combustion engine positioned within the hull. The place where the impeller shaft passes through the bulkhead normally is provided with an intermediate bearing that journals the impeller shaft. Of course, it is desirable to ensure that this intermediate bearing is lubricated.
Conventionally, arrangements have been provided wherein the intermediate bearing is a prepacked, sealed bearing or, alternatively, where the bearing is provided with a grease fitting so that it can be periodically lubricated. Both of these types of construction present some difficulties.
For example, if a sealed bearing is employed it must be ensured that the lubricant is quite thick so that it will not leak out and need repacking at frequent intervals. However, the thicker the lubricant, the less likely that the bearing will be adequately lubricated. Alternatively, if a grease fitting is employed, then this requires periodic maintenance by the operator including stopping of the engine and the provision of a grease gun to pressurize the bearing. Both of these expedients are not particularly advantageous.
It is, therefore, a principal object of this invention to provide an improved arrangement for lubricating the bearing of a water jet propulsion unit.
It is a further object of this invention to provide an improved lubricating system for the intermediate bearing of a jet propulsion drive for a watercraft.